Hassan Al-Thawadi, chief executive of Qatar's World Cup bid, says: 'Why do I have to prove my innocence when there is not a shred of evidence? Why should we have an investigation if no other country has one?' Photograph: AFP/Getty Images

When Sepp Blatter lifted the word Qatar from the envelope containing the host country for Fifa's 2022 World Cup, much of the football world was incredulous, while the Qatar bid team jumped all over each other in that Zurich hall. Hassan al-Thawadi, the small, fiery and, at 32, improbably young chief executive of Qatar's multimillion-dollar bid recalls the key moment differently. He says it was not 2 December but the day before, when he felt his team delivered a compelling final presentation to Fifa's inscrutable 22-man executive committee, which was the greatest moment of his life.

"Afterwards I broke down and cried," Thawadi recalls. "We had been all over the world, we took a bid nobody thought had much chance of winning on to a new level. I told my team on 1 December, win or lose, you should all be very proud."

He returned to Doha, Qatar's capital, tasked with forming a "supreme committee" to organise the tournament in the desert Gulf nation booming on vast reserves of natural gas, 25 trillion cubic metres, and the world's highest national earnings per citizen. Amid the relentless construction of new malls, vast hotels and yearning skyscrapers, Qatar must now build nine stadiums and remodel three more at a cost of $4bn-$5bn, and integrate the World Cup into Qatar's general transport and other infrastructure improvements planned to cost $150bn by 2030. They have committed to Fifa to address human rights issues and the appalling conditions many migrant workers have suffered building the Qatari air-conditioned consumer paradises, a progress which Thawadi pledges will be "accelerated" by the World Cup deadline.

Yet in the strikingly ordinary 2022 offices on the 26th floor of the Olympic tower in sweltering Doha's West Bay, the air is thick with frustration, which can make the project seem paralysed. Thawadi, in a long exclusive newspaper interview with the Guardian, denied that, saying they are currently tendering for programme managers to oversee the timetable for the Middle East's first World Cup. However, without doubt, a huge amount of energy is being spent raging against the claims of corruption levelled against the bid, and the guilt by association being experienced due to the bribery charges against Mohamed bin Hammam, the Qatari former president of the Asian Football Confederation, during his bid to replace Blatter as Fifa president.

"So much good can come out of this World Cup," Thawadi pleads. "Breaking down prejudices between the Arab world and the rest of the world, bringing people together, a profound legacy." He argues that Qatar is being singled out, that the wave of suspicion is partly fuelled by anti-Arab prejudice. "I'm asking the world to look at us rationally. There is no evidence behind any of these claims, not a sliver. Even if we had wanted to do anything improper, which we did not, we could not risk it because if it ever came out, the reputation of our whole country would be in tatters, the absolute opposite to what we are trying to achieve."

Qatar's campaign to host the World Cup was mounted with a huge budget – which Thawadi repeatedly refused to clarify, saying the big dollar number would become the story – partly as a "nation-building" exercise, to help cement and launch Qatar on the world stage. The components of this image the country wants to project, "Brand Qatar", are, according to the bid's head of communications, Nasser Alkhater: "Warmth, hospitality, economic development beyond oil and gas, openness to the world and being a positive interface between the Arab world and the rest of the world."

They believe, and campaigned, that a World Cup in Qatar, with stadiums and fan areas air-cooled from the stifling desert heat with new carbon-neutral technology, following 11 more years' development at Qatar's dizzying pace, will be enjoyable for players and supporters, and a landmark in Arab relations with the rest of the world.

Yet instead, the Qatar bid is in serious danger of having the very opposite effect on the country's reputation, spattered by claims that they won their 14 votes partly through corruption; wounded by that neat expression the secretary-general of Fifa himself, Jérôme Valcke, used in the email, leaked by former executive committee member Jack Warner, that Qatar "bought the World Cup".

As Thawadi deals with each in turn, it becomes clear that above everything else, the publication by the House of Commons select committee for culture, media and sport, of the letter from the Sunday Times has been, as Thawadi confirms, "the most damaging of all". It alleged, in a story the newspaper never printed, that "a whistleblower who had worked with the Qatar bid" had said the Qataris paid three African executive committee members, Issa Hayatou, Jacques Anouma and Amos Adamu, $1.5m for their votes.

On arrival in Doha, the Guardian was presented by Thawadi and Alkhater with the news that the whistleblower was retracting her story, saying she made it all up. They facilitated a conversation with her, then on Saturday evening she identified herself on a website specifically created for her retraction as Phaedra Almajid, formerly the international media specialist for the bid between May 2009 and March 2010. She explained she had been "furious" when the bid decided to move her from her job, which she loved, and decided to "hurt" the bid by fabricating the bribes story.

Almajid said she had come to feel "guilty" and "sorry" and wanted to apologise. Al-Thawadi understands abundantly how this could look – bluntly, that they pressured or paid Almajid. But both he and she insist this was not so, that she contacted the bid voluntarily, in despair at what she had done and feeling, given parliamentary exposure and a pledge by Fifa to investigate, that she was in over her head.

Besides this twist, the whistleblower blowing the whistle on her own story, Thawadi points out that the Sunday Times did not publish the story. Thawadi says he believes its publication by the select committee was unfair: "I do feel absolute surprise and disappointment. I understand and respect parliamentary privilege, but my country's reputation and my bid's reputation is being sullied, tarnished, because of these allegations."

The other Sunday Times stories relating to Qatar were based on filming by undercover reporters with aspiring fixers including Michael Zen-Ruffinen, the former Fifa secretary-general. Posing as representatives of the competing US bid, the fixers told reporters that Qatar was paying big money to executive committee members, particularly Africans. The Sunday Times said these allegations should have been investigated by Fifa. The select committee, in its report last month which said it was "appalled by the allegations of corruption," agreed.

The Qatari bid sent a detailed response which the select committee published. It pointed out that Zen-Ruffinen had immediately retracted his allegations, and arguing that the other middle men appeared to be "simply seeking to impress the supposed US representatives". The letter maintained that the allegations were false and backed by no evidence, that some had not been published in the newspaper.

"For those allegations to be propounded by the parliament of the United Kingdom is something we find distressing, insulting and incomprehensible," the letter said.

The select committee chairman, John Whittingdale MP, said he stands by the decision to publish, arguing that: "We did so not to say the allegations were true, but because Fifa was not prepared to investigate." The whistleblower's claims had not actually been presented to Fifa before the select committee published the story. But Thawadi says the Qatari bid team asked Fifa to investigate the claims because, he asserts: "We have nothing to hide and we did nothing wrong."

Then there is Bin Hammam, charged with bribery by Fifa's ethics committee, for allegedly paying delegates of Caribbean Football Union countries $40,000 each in cash to vote for him in the presidential election – just the wrong development for Qatar's efforts to wipe away the corruption allegations. Thawadi says Bin Hammam was not originally integral to their bid; he even took some time to win over. "We never went and gave him instructions. There is no connection to what is happening to him now, and what happened with us.

"And also remember: he too is innocent until proven guilty. And in our nature, as Arabs, as Qataris, we are not just going to abandon people for the sake of others in the world saying we should."

What is not disputed, however, was that in the latter stages Bin Hammam did lobby his fellow executive committee members to vote for Qatar. It would have been impossible for the bid to succeed without his influence. And there is the other scenario which some believe is the most likely, that influence was peddled above the bid team's head, by higher authorities in Qatar, a country wielding huge wealth and power around the world.

"People say this, that there was influence, that the Emir of Qatar became involved," responds Thawadi, enraged. "We are not a banana republic. All governments supported all bids, but we are asked if ours wielded influence. Why are you asking me that: because we are Arabs?"

That hits the soreness he says he is feeling. Thawadi repeatedly points out that Russia was awarded the 2018 World Cup "on the same day by the same Fifa executive committee after the same process", yet there have been no calls for its vote to be investigated.

He says he considered setting up an independent investigation, and was going to ask Mike Lee, the English consultant to the Qatar bid, to speak to Sebastian Coe about chairing it, but decided against it: "Why do I have to prove my innocence when there is not a shred of evidence? Why should we have an investigation if no other country has one? And what are you going to investigate? My books, my phone records, where I went, who I talked to, dig into my private life and everybody else's, and everybody who came into contact with Qatar? Are you going to look into the deal to buy Harrods, or our deal with Argentina for oil and gas, and dig into government affairs? Where does it stop?"

His overarching point is that Qatar has striven to present a persuasive case for a World Cup, "turning negatives to positives" as he puts it – air-cooled stadiums and fan areas to deal with heat in the 40s; stadiums which can be dismantled and rebuilt elsewhere, so there will be no herd of white elephant structures afterwards. A new train and metro system is to be built as part of the country's strategic plan to become a more sustainable economy beyond 2030. The bid spent $27m building a prototype stadium, containing just 500 seats and a five-a-side pitch, to trial a new carbon-neutral air-cooling system. For football fans to come from around the world to an Arab country for an activity as universally accessible and loved as football could be inspiring, he argues.

Yet Qatar, the unexpected choice of 14 out of the 22-man executive committee (two suspended for impropriety), were always going to be subject to doubts, given the corruption allegations which have beset Fifa itself, and the opacity of the bidding process. The members do not have to say how they voted, no reasons are given, and, astonishingly, they do not even have to visit the countries competing so expensively for the World Cup prize.

That, the murk of Fifa, is why an avalanche of suspicion has fallen on the Qatar decision in Zurich, as well as the mountain of work to do now in the rich desert land.

"I say stop the witch hunt and embrace the fact that this is a positive opportunity for the world," Thawadi, restless, says. "Look at the positive elements of a World Cup in the Middle East, especially in current circumstances. At the moment there is not a sliver of evidence we did anything wrong. If something real comes out, I'll shut up. I'll say: OK, and you can take the World Cup. How about that? "